[nanoPost] Nanostructured catalysts for the emission control systems

With respect to Emission Control, the institutes’s research activities are targeted to cost-effective, durable, Nanostructured catalysts for the emission control systems of the future. Such emission control systems will not only treat gaseous pollutants (CO, CxHy, NOx) but also particulate emissions - the attention from traditional 3-way catalysis has already shifted towards the so-called 4-way catalysis. The challenge in lean-burn-engine emission control is the effective simultaneous removal of NOx and soot particulates. Current state-of-the-art systems for the removal of these two pollutants are NOx traps and Catalyzed Diesel Particulate Filters.

Catalyzed Diesel Particulate Filters (C-DPFs): Soot particles today are retained inside a ceramic filter (known as Diesel Particulate Filter-DPF), the most common designs being based on an alternately plugged honeycomb structure that needs to be periodically regenerated by oxidation of the collected soot. Combustion of soot collected in particulate filters occurs at ~550°C in the absence of a catalyst. Novel materials to catalyze the process at low temperatures are highly desirable: mixed oxides like ABO3 perovskites and AB2O4 spinels with a nanometric structure, are the most promising to achieve the required performances and ageing resistance with a competitive cost. Aerosol Technologies can also be employed for the synthesis of nanostructured rare-earth based mixed spinels and perovskites.

NOx Traps: Current state-of-the-art systems for the reduction of Nitrogen oxides in diesel engines in the presence of high oxygen concentrations are ΝOx storage catalysts that incorporate doped barium oxide (BaO) and noble metals (Pt), oxidize NO into ΝΟ2 during lean operation and store it in the form of nitrate salts (Mx(NO3)y) on the catalyst sites. In order to fulfill emissions limits beyond 2005, there is a strong need for engine manufacturers to extend NOx storage capacity and temperature operating window. Aerosol Technologies can be employed for the production of BaO-based mixed oxide compositions with nano-sized structure containing stable alkali metals that will perform better than current state-of-the-art systems.

In the above perspective, the institute would like to collaborate on a specific results-oriented Project focusing on the utilization of Aerosol technologies as an alternative to current state-of-the-art synthesis routes, for the achievement of the physicochemical targets of the future Emission Control systems that current synthesis routes are not able to achieve, at competitive costs and sufficient quanti-ties.

The complete current state-of-the art exhaust after-treatment systems for lean-operating engines (diesel as well as gasoline) incorporate the suitable catalytic systems supported on three different substrates in series: DOCs, c-DPFs and NOx traps.

APTL aims to exploit Aerosol Decomposition Infiltration Technologies for simultaneous synthesis and deposition of all the catalytic nanoparticles on a single monolithic ceramic support, in a spatially controlled manner materializing the concept of 4-way catalysis for the lean burn engines of the future in a single piece.

A potential project could be structured along the following suggested tasks:

1 Aerosol Synthesis and Deposition of Nanostructured catalyst pre-prototypes for emission control systems of the future

2. Performance assessment of the integrated pre-prototype systems

3. Optimization of nanostructured catalyst formulations

4. Synthesis/deposition process scale up

5. Evaluation of final products